I just wanted to add that HDMI by itself is great, but it's not the entire story. The number of inputs in general is extremely important, the more inputs the better. You should look for sets that have at least 2 HDMI inputs, and 2 Component inputs, that way you don't need to buy a VERY expensive switcher. Of course if you get one of those cool A/V receivers then you don't really have that problem either. But still, it's a big pain in the butt when you have a bunch of devices that you want to connect and can't because of a lack of inputs, it's very easy to fill them up.
DVD player = 1 Component (1 HDMI if it's upscaling)
1 Video game console = 1 Component input
Your cable box = 1 component input (MAYBE an HDMI if it's new)
Then you want to connect your computer to your TV, where are you going to put it? Most computers don't have HDMI output, so you're stuck with low-res S-Video/Composite or taking up yet another Component input.
This is one of the nice things about next-gen consoles, the PS3 (the high-end version) has HDMI out, and upscales DVDs, plays Hi-Def Blu-Ray content, AND the normal PS3 games. So you can free up quite a bit of inputs with that $600 beast. Even the 360 gives some outlet as you can hook it up to your tv with VGA (if your tv has the input). This has the extra-nice side effect of allowing the 360 to perform DVD upscaling, as it can only upscale through VGA output and not over Component, thank you Hollywood /sarcasm. As for the Wii, it will be able to play DVD movies as well, but no upscaling, and it's not even going to be hi-def. Lame Nintendo, very lame.